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AN OVERBROAD PATENT ON tracking and managing group expenditures - This application from Google seeks to patent the idea of...dividing expenses among members of a group! 10 minutes of your time can help narrow US patent applications before they become patents. Follow @askpatents on twitter to help.

Originally filed by Google on March 30, 2012, made public Oct 3, 2013.

A method for tracking payment transactions of a group of users, comprising:

establishing, by a computer system a group including at least three users;

maintaining, by the computer system, a transaction record for the group including a plurality of payment transactions involving the users of the group, each of the plurality of payment transactions associated with a payment amount;

responsive to receiving information on a payment transaction involving a user of the group and associated with a payment amount, determining, by the computer system, whether the payment transaction occurred within a range of dates provided for the group;

responsive to determining the payment transaction occurred within the range o dates, updating, by a computer system, the transaction record for the group to include the payment transaction;

updating, by the computer system, a total balance maintained for the transaction record based on payment amounts associated with the payment transactions included in the transaction record; and

responsive to a settlement event, settling, by the computer system, the total balance by initiating fund transfers between the users of the group for the payment transactions occurring within the date range

In English the means:

A method for tracking payment transactions of a group of users, comprising:

Establishing a group of at least three users;

Maintaining a transaction record for the group which includes at least one payment transaction among group members and a payment amount for that transaction;

Receiving information about a payment transaction involving the group that occurs within a range of dates provided for by the group.

Updating the transaction record for the group to include the payment transaction;

Updating a total balance maintained for the transaction record; and

Settling the total balance by initiating fund transfers between the users of the group.

Good prior art would be evidence of a system that did each and every one of these steps prior to 3/30/2012

"Fig 4. A table illustrating balances of users of a group" from the Applicant

IMO, SpotMe Payments (#1) is similar enough to the patent, but (like mine?) lacks "initiating a fund transfer" (step 6), the others look like they are just intended for a single event, so that only covers step 5?
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McKayOct 9 '13 at 13:42

Short Reckonings. www.shortreckonings.com. I've been using them since at least summer 2010. Google has basically described exactly the function that SR performs. You go somewhere with a group of friends. You pay for bills as they come up, and later you punch the bills into SR, and it figures out who owes what to who. Even for uneven splits. Google's late to the party.

I have been writing my own code to do this for several years. I think the first version that covered "includes a plurality of payment transactions." was built in 45 minutes on 3 June 2010 (according to google's version history)

Here is a screenshot about what it looked like on that day:

The first line is the information header,
the second line is the current balance header
Each subsequent line represents an item with amounts and running totals.
The first four columns are user-editable. The columns with running totals are automatically calculated based on the data in the first four columns.

In the example below, "McKay" paid 600, and each of four individuals used said items split equally.
Then Mark paid 497 dollars split equally between McKay and Mark.
The system knows who is owed what (but it doesn't matter to who). Shyra needs to pay 150, Sean needs to pay 150, and McKay and Mark are each owed different amounts.

This is made available to everyone in the group. From any of their devices compatible with google's services.

I use code like this every time I go on a group trip, and because it took 45 minutes to write, I considered it obvious, and non-patentable.

By the end of the trip, it looked like this:
As you can see, Sean and Shyra didn't end up going, and Mark and Steve took their place. Cash and Check lines indicate when one person paid another (as indicated) to clear out their balances after the trip was over.

I cover all the pieces of Claim 1, as well as some of the other claims. You might want to make sure to refer to the amended version, which I just linked to, and you can also find on "Public Pair" of the USPTO by searching this publication number.

CLAIM 1:

Bullets 1&2: Establish at least a group of three users sharing a total balance in a group, with a list of transactions and payments, and have the list of transactions and total balance list be reactive to payment transactions added by group members.

Bullet 3: Using a range of dates was used for recurring expenses in SplitMyBill.ie, and done in a couple ways at Splitwise prior to 2012.

SplitMyBill.ie, Apr 2009: Wayback Machine / SplitMyBill.ie Tour
Splitwise, Mar 5th 2012: Splitwise Blog. Splitwise uses a date range to sort balances into monthly totals within each group.
Splitwise, Dec 2011: Forbes / Splitwise Blog. Splitwise publishes a calculator that uses a range of dates to tell how a given expense should be divided among which members of a group.

Other Claims

Looking at the patent as amended*, we should also look at Claims 2, 6, and 10. Claims 11-25 are basically variations on a theme, with the phrases "computer software" exchanged with "method" or "system" or the idea of "additional users" added to the other claims. The idea of an "additional user" (doing something as part of an invitation, does this mean?) being able to do things was a feature in BillMonk, SplitMyBill.ie, Splitwise, and others, and combining that with other features is probably fairly obvious to someone skilled in the art.

CLAIM 2: Individual Balances

Claim 2 brings in the idea of "individual balances", as distinct from "total balances," which could mean non-total balances as shown in Figure 4. But Billmonk pioneered the idea that you could track both individual and total balances within the group and reduce it to a total balance at the users discretion.
Billmonk, Aug 2007: Billmonk Blog

CLAIM 6-9Claim 1 + "inquiring from the additional user whether to add the additional payment transaction to the record", "responsive to a user device", and "electronic system of a financial account".

This was all done by PayDivvy. In the screenshot below, you can see the connections to real bank accounts, from a user device (a laptop), with a permission based system for new bills.

Balance-based: May be the only claim in the patent that is not built in a pre-existing product, though someone may have described it in a press article or interview.

FIGURE 4

Billmonk was the first to widely publicize the simplification of a set of "X owes Y" into its simplest form, but the feature is also in Splitwise, Billsup, and many other apps. Look at this image from the Billmonk Blog in August 2007 and compare it to the official Figure 4.